Potential effects of global atmospheric CO/sub 2/ enrichment on the growth and competitiveness of C/sub 3/ and C/sub 4/ weed and crop plants. [Zea mays; Abutilon theophrasti; Glycine max; Rottboellia]

Journal Article · Tue Jan 01 04:00:00 EST 1980 · Weed Sci.; (United States)

OSTI ID:6805523

Patterson, D T; Flint, E P

Mathematical growth analysis techniques were used to evaluate the effects of CO/sub 2/ concentrations of 350, 600, and 1000 ppm (v/v) on growth and biomass partitioning in corn (Zea mays L. Dekalb (L 395'), itchgrass (Rottboellia exaltata L.f.), soybean (Glycine max L) Merr. Tracy), and velvetleaf (Abutilon theophrasti Medic.). Controlled environment chambers with day/night temperatures of 28/22 C and photosynthetic photon flux densities (PPFD) of 650 ..mu..E (microeinteins) m/sup -2/ s/sup -1/ were used. Dry matter production in the two C/sub 3/ species soybean and velvetleaf) was increased significantly by raising the CO/sub 2/ concentration above 350 ppm. In corn (a C/sub 4/ species), dry matter production was greatest at 600 ppm CO/sub 2/ and did not differ between the 350 and 1000 ppm treatments. Increasing the CO/sub 2/ concentration increased the rate of dry matter production per unit leaf area (net assimilation rate or NAR) in soybean and velvetleaf but either decreased or did not alter NAR in corn and itchgrass. At 45 days after planting, the weed/crop ratios for total dry matter production for velvetleaf/corn and itchgrass/corn were significantly greater at both 600 and 1000 ppm than at 350 ppm CO/sub 2/. The weed/crop ratio for itchgrass/soybean was less at 1000 ppm than at 350 or 600 ppm CO/sub 2/. Compared to the value at 350 ppm, the weed/crop ratio for velvetleaf/soybean was greater at 600 ppm and less at 100 ppm CO/sub 2/.

• Research Organization: Dept. of Agriculture, Stoneville, MS
• OSTI ID: 6805523
• Journal Information: Weed Sci.; (United States), Journal Name: Weed Sci.; (United States) Vol. 28:1; ISSN WEESA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ATMOSPHERES
BACTERIA
BIOLOGICAL EFFECTS
BIOLOGICAL PATHWAYS
C4 SPECIES
CALVIN CYCLE SPECIES
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CEREALS
CHALCOGENIDES
CHEMICAL REACTIONS
CONTROLLED ATMOSPHERES
CROPS
ECOLOGICAL CONCENTRATION
GLYCINE HISPIDA
GRASS
GROWTH
LEGUMINOSAE
MAIZE
MICROORGANISMS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANT GROWTH
PLANTS
RHIZOBIUM
SYNTHESIS